Glioneuronal tumors in childhood - Before and after surgery. A long-term follow-up study

Low-grade epilepsy-associated neuroepithelial tumors: Tumor spectrum and diagnosis based on genetic alterations

Brain tumors can always result in seizures when involving the cortical neurons or their circuits, and they were found to be one of the most common etiologies of intractable focal seizures. The low-grade epilepsy-associated neuroepithelial tumors (LEAT), as a special group of brain tumors associated with seizures, share common clinicopathological features, such as seizure onsets at a young age, a predilection for involving the temporal lobe, and an almost benign course, including a rather slow growth pattern and thus a long-term history of seizures. Ganglioglioma (GG) and dysembryoplastic neuroepithelial tumor (DNET) are the typical representatives of LEATs. Surgical treatments with complete resection of tumors and related epileptogenic zones are deemed the optimal way to achieve postoperative seizure control and lifetime recurrence-free survival in patients with LEATs. Although the term LEAT was originally introduced in 2003, debates on the tumor spectrum and the diagnosis or classification of LEAT entities are still confusing among epileptologists and neuropathologists. In this review, we would further discuss these questions, especially based on the updated classification of central nervous system tumors in the WHO fifth edition and the latest molecular genetic findings of tumor entities in LEAT entities.

The long-term surgical outcomes of low-grade epilepsy-associated neuroepithelial tumors

OBJECTIVE

This study aimed to evaluate the surgical outcomes and relevant prognostic factors in patients with low-grade epilepsy-associated neuroepithelial tumors (LEAT) and, especially, to develop a scoring system to predict postoperative seizure outcomes.

METHODS

The clinical data of patients who underwent epilepsy surgery for LEAT were retrospectively studied. The surgical outcomes of seizure and neurological statuses in patients were evaluated using Engel classification and modified Rankin Scale (mRS) scoring, respectively. A scoring system of seizure outcomes was constructed based on the weight of the β-coefficient estimate of each predictor in the final multivariate predicting model of seizure outcomes.

RESULTS

Of the 287 patients (106 female) enrolled, the median age was 19 years at surgery and 10 years at seizure onset, with a median duration of epilepsy of 60 months. Among 258 patients who were followed up for at least 12 months, 215 (83.3%) patients had a favorable seizure outcome (Engel class I) after surgery, and 43 (16.7%) patients had an unfavorable seizure outcome; longer duration of epilepsy, discordant magnetoencephalography (MEG) findings, and acute postoperative seizures were significantly included in the scoring system to predict unfavorable seizure outcomes, and in the scoring system, accumulated scoring of 0-19 scores was recorded, which were finally grouped into three risk levels: low risk (risk < 30%), medium risk (30% ≤ risk < 70%), and high risk (risk ≥ 70%). In addition, favorable neurological outcomes (mRS score 0-1) were recorded in 187 (72.5%) patients, while unfavorable neurological outcomes were recorded in 71 (27.5%) patients, which were significantly related to poor seizure control, older age at surgery, and longer duration of epilepsy and hospitalization time.

SIGNIFICANCE

The long-term surgical outcomes of LEAT after surgery were satisfactory. A scoring system for predicting unfavorable seizure outcomes with different risk levels was developed, which could partly guide clinical treatments of LEAT.

Quantifying and Reporting Outcomes in Pediatric Epilepsy Surgery: A Systematic Review

OBJECTIVE

Several instruments and outcomes measures have been reported in pediatric patients undergoing epilepsy surgery. The objective of this systematic review is to summarize, evaluate, and quantify outcome metrics for the surgical treatment of pediatric epilepsy that address seizure frequency, neuropsychological, and health-related quality of life (HRQL).

METHODS

We performed a systematic review according to PRISMA guidelines to identify publications between 2010 and June 2021 from PubMed, Embase, and the Cochrane Database of Systematic Reviews that report clinical outcomes in pediatric epilepsy surgery.

RESULTS

Eighty-one papers were included for review. Overall, rates of post-operative seizure frequency were the most common metric reported (n= 78 studies, 96%). Among the seizure frequency metrics, the Engel Epilepsy Surgery Outcome Scale (n= 48 studies, 59%) was most commonly reported. Neuropsychological outcomes, performed in 32 studies (40%) were assessed using 36 different named metrics. Health-Related Quality of Life (HRQL) outcomes were performed in 16 studies (20%) using 13 different metrics. Forty-six studies (57%) reported postoperative changes in anti-epileptic drug (AED) regimen and time-to-event analysis was performed in 15 (19%) studies. Only 13 outcomes metrics (1/5 seizure frequency, 6/13 HRQL, 6/36 neuropsychological) have been validated for use in pediatric patients with epilepsy and only 13 have been assessed through reliability studies (4/5 seizure frequency, 6/13 HRQL, and 3/36 neuropsychological). Of the 81 included studies, 17 (21%) used at least one validated metric.

SIGNIFICANCE

Outcome variable metrics in pediatric epilepsy surgery are highly variable. While nearly all studies report seizure frequency, there is considerable variation in reporting. HRQL and neuropsychological outcomes are less frequently and much more heterogeneously reported. Reliable and validated outcomes metrics should be used to increase standardization and accuracy of reporting outcomes in pediatric patients undergoing epilepsy surgery.

Epilepsy surgery for low-grade epilepsy-associated neuroepithelial tumor of temporal lobe: a single-institution experience of 61 patients

Background

Low-grade epilepsy-associated neuroepithelial tumor (LEAT) is highly responsive to surgery in general. The appropriate surgical strategy remains controversial in temporal LEAT. The aim of this study is to analyze the surgical seizure outcome of temporal LEAT, focusing on the aspects of surgical strategy.

Methods

Sixty-one patients from a single epilepsy center with temporal LEAT underwent surgery. The surgical strategy was according to the multidisciplinary presurgical evaluation. Electrocorticogram (ECoG)-assisted resection was utilized. Surgical extent including lesionectomy and extended resection was described in detail. Seizure outcome was classified as satisfactory (Engel class I) and unsatisfactory (Engel classes II–IV).

Results

After a median follow-up of 36.0 (30.0) months, 83.6% of patients achieved satisfactory outcome, including 72.1% with Engel class Ia. There was 39.3% (24/61) of patients with antiepileptic drug (AED) withdrawal. Use of ECoG (χ2 = 0.000, P > 0.1), preresection spike (χ2 = 0.000, P = 0.763), or spike residue (P = 0.545) was not correlated with the seizure outcome. For lateral temporal LEAT, outcome from lesionectomy was comparable to extended resection (χ2 = 0.499, P > 0.1). For mesial temporal LEAT, 94.7% (18/19) of patients who underwent additional hippocampectomy were satisfactory, whereas only 25% (1/4) of patients who underwent lesionectomy were satisfactory (P = 0.009).

Conclusion

Surgical treatment was highly effective for temporal LEAT. ECoG may not influence the seizure outcome. For lateral temporal LEAT, lesionectomy with or without cortectomy was sufficient in most patients. For mesial temporal LEAT, extended resection was recommended.

Factors associated with seizure and cognitive outcomes after epilepsy surgery for low-grade epilepsy-associated neuroepithelial tumors in children

Low-grade epilepsy-associated neuroepithelial tumors (LEATs) are responsible for drug-resistant chronic focal epilepsy, and are the second-most common reason for epilepsy surgery in children. LEATs are extremely responsive to surgical treatment, and therefore epilepsy surgery should be considered as a treatment option for LEATs. However, the optimal time for surgery remains controversial, and surgeries are often delayed. In this review, we reviewed published article on the factors associated with seizure and cognitive outcomes after epilepsy surgery for LEATs in children to help clinicians in their decision whether to pursue epilepsy surgery for LEATs. The achievement of gross total resection may be the most important prognostic factor for seizure freedom. A shorter duration of epilepsy, a younger age at surgery, and extended resection of temporal lobe tumors have also been suggested as favorable prognostic factors in terms of seizure control. Poor cognitive function in children with LEATs is associated with a longer duration of epilepsy and a younger age at seizure onset.

Somatostatin receptor expression and mTOR pathway activation in glioneuronal tumours of childhood

PURPOSE

To investigate the expression of somatostatin receptors (SSTRs) and markers of mTOR pathway in paediatric glioneuronal tumours and correlate these findings with tumour type, BRAFV600E mutational status and clinical characteristics such as tumour location, seizure frequency and duration, and age.

METHOD

37 children and adolescents with a neuropathological diagnosis of glioneuronal tumour were identified over a 22-year period. Immunohistochemical analyses for SSTRs type 1, 2A, 3, 5 and ezrin-radixin-moesin (ERM) and phosphorylated S6 (pS6), which are indicators of mTOR pathway activation, were performed in tumour specimens from 33 patients and evaluated using the immunoreactive score (IRS). The IRS were compared to tumour type, BRAFV600E status and clinical characteristics.

RESULTS

Ganglioglioma (GG) was the most frequently encountered subgroup (n = 27), followed by dysembryoplastic neuroepithelial tumour (DNET; n = 4). GGs expressed SSTR2A and SSTR3 to a high extent, 56 % and 44 % respectively. Expression of SSTR2A was also found in DNETs. Signs of mTOR pathway activation were abundant in GGs, but only present in one DNET. No correlations with BRAFV600E presence or clinical characteristics were found.

CONCLUSIONS

Expression of SSTRs and activation of mTOR pathway in paediatric glioneuronal tumour suggest that somatostatin analogues and mTOR inhibitors may have potential therapeutic implications in a subset of inoperable childhood glioneuronal tumours causing medically refractory epilepsy and/or tumour growth. Further clinical studies are warranted to validate these findings.

Social attainment in survivors of pediatric central nervous system tumors: a systematic review and meta-analysis from the Children's Oncology Group

PURPOSE

Improved therapies for pediatric central nervous system (CNS) tumors have increased survival rates; however, many survivors experience significant long-term functional limitations. Survivors of pediatric CNS tumors can experience deficits in social attainment. The aim of this review was to systematically amalgamate findings pertaining to social attainment (i.e., educational attainment, marriage, employment outcomes) in survivors of pediatric CNS tumors.

METHODS

PubMed (web-based), PsycINFO (EBSCO), EMBASE (Ovid), and Web of Science (Thomson Reuters) were used to identify articles published between January 2011 and September 2018. Eligible studies reported outcomes for survivors of pediatric CNS tumors diagnosed before age 21 years and > 5 years from diagnosis and/or > 2 years off therapy. All data were independently abstracted by two reviewers. Random-effects meta-analyses were performed using Review Manager 5.0.

RESULTS

The search yielded 7021 unique publications. Forty-six were included in the current review. Meta-analyses revealed survivors of CNS tumors were significantly more likely to have completed compulsory education only (OR = 1.87, 95% CI = 1.66, 2.12, p < 0.00001), less likely to be married (OR = 4.70, 95% CI = 3.89, 5.68, p < 0.00001), and more likely to be unemployed (OR = 2.84, 95% CI = 2.62, 3.08, p < 0.00001) compared to non-cancer controls. Cranial radiation therapy, neurocognitive deficits, and younger age at diagnosis were associated with poorer outcomes. Hearing loss and bilateral blindness were also related to poorer outcomes. Sex did not impact social attainment outcomes.

CONCLUSIONS

Survivors of pediatric CNS tumors are at elevated risk for poor attainment of key adult social outcomes.

IMPLICATIONS FOR CANCER SURVIVORS

There is a critical need to develop interventions to support survivors in becoming independent and productive adults.

Social outcomes for adults with a history of childhood-onset epilepsy: A systematic review and meta-analysis

OBJECTIVES

This review aimed to describe social outcomes in adulthood for people with a history of childhood-onset epilepsy and identify factors associated with these outcomes; focused on educational attainment, employment, income/financial status, independence/living arrangement, romantic relationships, parenthood, and friendships.

METHODS

A comprehensive search of MEDLINE, EMBASE, and PsycINFO was conducted, as well as forward and backward citation tracking. A total of 45 articles met inclusion criteria. Random effects meta-analyses were conducted, and subgroup analyses evaluated outcomes for people with epilepsy (PWE) with good prognosis (e.g., normal intelligence, 'epilepsy-only') and poor prognosis (e.g., intellectual disability, Dravet syndrome), and those who underwent epilepsy surgery in childhood.

RESULTS

Among all PWE, 73% (95% confidence interval [CI]: 64-82%) completed secondary school education, 63% (95%CI: 56-70%) were employed; 74% (95%CI: 68-81%) did not receive governmental financial assistance; 32% (95%CI: 25-39%) were in romantic relationships; 34% (95%CI: 24-45%) lived independently; 21% (95%CI:12-33%) had children, and 79% (95%CI: 71-87%) had close friend(s). People with epilepsy often fared worse relative to healthy controls. Among PWE with a good prognosis, a comparable number of studies reported similar/better outcomes relative to controls as reported poorer outcomes. The most consistent predictor of poorer outcomes was the presence of cognitive problems; results of studies evaluating seizure control were equivocal.

CONCLUSION

People with epilepsy with a good prognosis may show similar social outcomes as controls, though robust conclusions are difficult to make given the extant literature. Seizure control does not guarantee better outcomes. There is a need for more studies evaluating prognostic factors and studies with control groups to facilitate appropriate comparisons.

Epilepsy Surgery for Children With Low-Grade Epilepsy-Associated Tumors: Factors Associated With Seizure Recurrence and Cognitive Function

OBJECTIVE

Low-grade epilepsy-associated tumors (LEATs) are associated with childhood seizures that are typically drug-resistant, necessitating surgical interventions. In this study, we aimed to investigate the efficacy of surgical intervention in children with LEATs and to identify factors associated with seizure and cognitive outcomes.

METHODS

We reviewed 58 children less than 18 years of age who underwent epilepsy surgery due to histopathologically confirmed LEATs and had a minimum postoperative follow-up duration of 24 months.

RESULTS

Of the 58 patients who were followed for a median duration of 5.6 (IQR 3.2 to 10.0) years, 51 (87.9%) were seizure-free after surgery. In univariate analysis, shorter epilepsy duration, fewer antiepileptic drugs at time of surgery, gross total resection, and unilobar tumor involvement were associated with seizure freedom. In multivariate analysis, gross total resection was independently associated with seizure freedom. The preoperative and postoperative full-scale intelligence quotient (FSIQ) scores were 78.9 ± 27.1 and 80.9 ± 28.7, respectively. In univariate analysis, younger age at seizure onset, longer epilepsy duration, more antiepileptic drugs at time of surgery, multilobar tumor involvement, and presence of generalized epileptic discharges were associated with lower preoperative FSIQ. In multivariate analysis, longer epilepsy duration was independently associated with lower preoperative FSIQ scores. Postoperative FSIQ scores were significantly influenced by preoperative FSIQ scores.

CONCLUSIONS

Epilepsy surgery for LEATs in children resulted in excellent seizure outcome. Gross total resection was the only independent factor associated with favorable seizure outcome. Preoperative and postoperative cognitive abilities were significantly influenced by epilepsy duration, so early surgical intervention should be considered.

Cognition, health-related quality of life, and mood in children and young adults diagnosed with a glioneuronal tumor in childhood

AIMS

The aim of this study was to investigate long-term cognitive outcome, health-related quality of life (HRQoL), and psychiatric symptoms in children and young adults diagnosed with a glioneuronal tumor in childhood.

METHODS

Twenty-eight children and adolescents (0-17.99years) with a minimum postoperative follow-up time of five years were eligible for the study; four persons declined participation. A cross-sectional long-term follow-up evaluation was performed using the following study measures: Wechsler Intelligence Scale for Children (WISC-IV) or Wechsler Adult Intelligence Scale (WAIS-IV), Reys Complex Figure Test (RCFT), Short Form 36 version 2 (SF-36v2), Short Form 10 (SF-10), Quality of Life in Epilepsy 31 (QOLIE-31), Hospital Anxiety Depression Scale (HADS) or Beck Youth Inventory Scales (BYI), and Rosenberg Self-Esteem Scale. Historical WISC-III and RCFT data were used to compare cognitive longitudinal data.

RESULTS

Mean follow-up time after surgery was 12.1years. Sixty-three percent (15/24) were seizure-free. Despite a successive postoperative gain in cognitive function, a significant reduction relative to norms was seen in the seizure-free group with respect to perceptual reasoning index (PRI), working memory index (WMI), and full-scale intelligence quotient (FSIQ). Seizure freedom resulted in acceptable HRQoL. Thirty-two percent and 16% exceeded the threshold level of possible anxiety and depression, respectively, despite seizure freedom.

CONCLUSION

Although lower than in corresponding reference groups, cognitive outcome and HRQoL are good provided that seizure freedom or at least a low seizure severity can be achieved. There is a risk of elevated levels of psychiatric symptoms. Long-term clinical follow-up is advisable.